Aim: Obesity increases a person’s susceptibility to infections due to a combination of factors including increased bacterial colonization, skin folds which promote bacterial growth, and insufficient wound cleaning. Obesity is an independent risk factor for surgical site infections (SSI) post abdominal surgical procedures1. In obese women the odds ratio for post-cesarean surgical site infections increases by 2.0 for every five-unit increment in body mass index2. Rates of obesity in Canada continue to increase, making it imperative for clinicians and patients to be aware of wound cleaning measures that reduce risk of surgical site infections in this population. Detecting bacterial presence based on clinical signs and symptoms is difficult as bacteria are invisible to the naked eye. To address this problem, autofluorescence imaging has recently been used to visualize pathogenic bacteria in real-time at the bedside using a non-contact hand held device3. Herein, we report the use of this device to detect and monitor the presence of bacteria in obese surgical site infection patients and guide clinician and patient wound cleaning regimes.

Methods: Surgical site infection patients (2 abdominal surgeries, 1 caesarean section) were imaged with the autofluorescence imaging device prior to and post-surgical site cleaning during routine wound care visits to monitor the presence of bacteria, guide wound cleaning, and educate the patients on home care cleaning practices.

Results: Surgical site infections that fluoresced red were considered positive for bacteria and received additional cleaning. Images were used to educate patients on the presence of bacteria, which was located both at and in the vicinity of their surgical site, and to raise awareness about infection. The bright and simple colors on fluorescence images (green = tissue, red = bacteria) made it easy for patients to understand when and where bacteria was present. Patients were counseled on at home cleaning practices that should regularly be performed (eg. lifting of skin folds, cleaning at and around the surgical site). An improvement in patient compliance was observed.

Applications: Fluorescence images revealing the presence of bacteria guided the extent and location of clinician cleaning. Visualizing bacteria, which the patient otherwise could not have seen, provided enhanced awareness of their SSI. These results highlight the potential of this imaging tool to improve understanding and compliance with home cleaning protocols in the obese patient population.